HONG KONG, Oct 30 (Reuters) - Asia-focused bank Standard Chartered said its operating profit grew by a mid-single digit rate in the first nine months of the year, putting it on track for a 10th straight year of record earnings.

Earnings would have risen by at least 10 percent if not for a $340 million settlement paid to New York regulators who threatened to strip the bank of its state licence over allegations it hid some $250 billion worth of transactions with Iran.

``Although the environment remains turbulent, we are in the right markets and continue to see good momentum across our businesses and geographies,'' CEO Peter Sands wrote in a third-quarter trading update on Tuesday.

The bank's forecast is roughly in line with full-year expectations for a 6 percent rise in pretax profit to about $7.2 billion, according to Thomson Reuters I/B/E/S. It does not release specific numbers in its quarterly updates.

Rising household debt in South Korea - which now exceeds that of the United States before the subprime mortgage crisis - has prompted worries the country may soon see a spike in bad loans. In Singapore, the city-state narrowly escaped a recession in the third quarter.

Despite the slowdown, Standard Chartered said it reduced how much it put aside in case of bad loans - its impairment charge - by tens of millions of dollars. In the first half of the year, the bank set aside $583 million for impairment charges.

Standard Chartered said portfolio quality in its wholesale bank - which includes its investment bank and commercial bank - was good, though it was watchful in India and the Middle East.

Questions about Standard Chartered's asset quality arose after the bank made a $1 billion loan to the Indonesian chairman of London-listed Bumi Plc, triggering some concern over the bank's lending practices.

Costs remained under control, with revenue growth roughly in line with the increase in costs - a trend known as ``neutral jaws''. Standard Chartered was bogged down by rising costs in much of 2010 and 2011 as it expanded across Asia.